Conventionally, there is known an antenna device that receives electric waves by using a plurality of film antennas (plane-shaped antennas) attached to, for example, a front window of a vehicle. When this antenna device receives electric waves of, for example, Digital Television (DTV) and the like, all of the plurality of antennas are constituted of loop antennas (see Japanese Laid-open Patent Publication No. 2009-267992, for example).
However, an attachment area of the above loop antennas is comparatively large, and thus, in a case of an antenna device all the antennas of which are constituted of loop antennas, an attachment area of the loop antennas on a front window becomes large, as a result, there exists a fear that an area for attaching another apparatus such as an on-vehicle camera is not secured. Thus, the conventional technology has room for improvement in reducing the attachment area of the antenna device.